Corrosion Resistance of the Surfac Recrystallized Alloy 182 Weld Metal by Cold Working and Laser Irradiation

摘要

Intergranular corrosion (IGC) and intergranular stress corrosion cracking (IGSCC) of the recrystallized Alloy 182 weld metal containing 0.05 percent C have been investigated. Cold rolled Alloy 182 was recrystallized by electric furnace heating or by YAG (Yttrium-Aluminum-Garnet) laser irradiation. IGC resistance and IGSCC resistance were evaluated by Streicher test (JIS G 0572) and by Crevied Bent Beam test in the 288 deg C hot water respectively. It was observed that the 60 percent cold rolled Alloy 182 is occupied by the recrystallized gains after the electric furance heating at 800 to 900 deg C, and the recrystallized Alloy 182 is excellent in IGC resistance. By YAG laser irradiation, surface recrystallized layer of about 400 to 500 mu m thickness can be formed on the cold rolled Alloy 182. Corrosion resistance of the surface recrystallized Alloy 182 is also excellent, because of the granular Cr-rich carbides distribution in the recrystallized grains.